The clutch & the muffler will not affect the oil consumption, I have customers here in Australia using 20W-50 and our summers can be in the 40Deg range, I have added oil company notes refer to 20W-50 specs to see if this suits your needs.
SAE Viscosity Grade Motor Oil: 10W-40
Temperature Conditions: Above 0 F
Description: The first multi grade introduced. A good choice for controlling engine wear and preventing oil breakdown from oxidation.
SAE Viscosity Grade Motor Oil: 20W-50
Temperature Conditions: Above 20 F
Description: Provides maximum protection for high-performance, high-RPM racing engines. Excellent choice for high temperature and heavy loads such as driving in the desert or towing a trailer at high speeds for long periods of time.
SAE Viscosity Grade Motor Oil: SAE 30 & SAE 40
Temperature Conditions: Above 40 F & Above 60 F
Description: For cars and light trucks, where recommended by manufacturers. Not recommended when cold-temperature starting is required.
Tuesday, July 13th, 2010 AT 4:23 AM